Vacuum cleaners generally include a motor which drives an air impeller to create a low pressure area inside of a tank or other receptacle. The tank has an inlet through which dust and debris or liquid material enter into the tank, usually from a hose. The incoming airstream flows through the tank and exits out one or more exhaust ports.
During dry pick-up, the dust or debris may pass into the air impeller, thereby interfering with operation of the air impeller or motor. In addition, the dust or debris may be exhausted back out into the room. To address the problems associated with the particulate-laden airstream, previous vacuum cleaners have typically included a filter for use during dry pick-up to collect the particulate material. Cylindrical or cartridge filters are often used which have large filtering surface areas and may be made of a variety of filtering materials.
The particulate matter collected by the filter may eventually result in clogging of the filter so that it must be cleaned or changed. Traditionally, a vacuum has had to be taken apart in order to access and clean a clogged filter. This process is time consuming and inconvenient. Additional developments are desirable in order to easily and effectively clean a filter without taking apart the vacuum.